PCB contact arrangement

ABSTRACT

A printer circuit board for mounting electrical components such as LEDs has outward edge protrusion on which an electrically conductive material is deposited such that the board itself can be used to make electrical contact in a pre-existing, commercially available fitting, such as a screw-in or base fitting designed to receive incandescent light bulbs. For a screw-in fitting the board can optionally be made slightly wider than the inner diameter of the fitting but be provided with at least one axially extending slit; the board is then compressed slightly but biased outward to provide better electrical contact when inserted into fitting.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional and claims priority of U.S. patentapplication Ser. No. 10/714,761 (“Bi-Directional LED-Based Light”),filed 17 Nov. 2003 now U.S. Pat. No. 7,053,560.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to lights that use multiple light-emittingdiodes, as well as to fixtures for mounting such lights.

2. Description of the Related Art

Incandescent light bulbs are commonly used for indicator lamps, tasklamps, general lighting, decorative lamps, warning lamps, traffic lampsand the like. However, incandescent bulbs, and to a lesser extent evenplasma-based fluorescent and halogen lights, are generally inefficientin terms of energy use and are subject to frequent replacement due totheir limited lifetime. Significant savings can be made by the use lightbulbs where the source of light is light-emitting diodes (LED).

LEDs are much more efficient (in terms of lumens per watt) thanincandescent and fluorescent lights; moreover, LEDs generally last muchlonger. This is particularly true of the class of LEDs known as“super-luminescent” or “super-bright,” which have already found uses insuch applications as automobile tail lights and traffic signal lights.

Being diodes, one problem with LEDs is that they are direct-current (DC)devices that are easily damaged by too high reverse voltage, whereas thepower supplies for many devices that would benefit from the advantagesof LEDs deliver alternating current (AC). Even low-voltage lightfixtures typically use a 12V AC power source, which is transformed from,for example, 120V AC at 60 Hz.

One common way to provide direct current to LEDs from an AC source is toinclude in the power-supply circuit a full-wave rectifier and acurrent-limiting device such as a power resistor. One drawback of thisapproach is that four rectifying diodes are typically needed and each ofthese rectifying diodes must carry half the full current load of all theLEDs.

Another known way to provide DC current to LEDs is to include in thepower-supply circuit a half-wave rectifier and, again, acurrent-limiting device such as a power resistor. This is a much simplercircuit than is needed for full-wave rectification, but even it has atleast three major drawbacks: First, the light emitted from the LEDs willflicker, for example, at 120 Hz in case the AC power source frequency is60 Hz. Second, when the supplied voltage is negative, this circuitassumes that the LEDs will evenly divide the reverse voltage amongthemselves. Failure to do so can lead to a cascade failure of the LEDs;this failure is most prominent in transient conditions. Third, therectifying diode must carry the full current load of the LEDs.

Even assuming that the power supply problems of the LEDs are overcome,there must still be some convenient way to mount and install the lightsthemselves. There are of course many different types of light fixturesfor the many different common types of incandescent light bulbs. Thesefixtures feature an array of different types of physical connectionswith wedge, screw-in, bayonet, flange, bi-pin and other bases. Thismeans that any after-market LED-based light bulb replacement must beable to correctly connect to the different types of existing sockets ofthe bulbs it is intended to replace. It would be possible to mount LEDunits within the casings—usually bulbs—of the original lights, but thiscomplicates the manufacture of such LED replacements.

Yet another concern is that incandescent elements can typically bemounted without regard to polarity, whereas existing LED arrangementscannot. When installing an LED replacement in a DC system such as anautomobile tail light, there is therefore a risk of incorrectinstallation because even with a given fitting, the polarity of thewiring is not always the same from one car manufacturer to another.

What is needed is an LED lighting arrangement that eliminates or atleast reduces the problems mentioned above. Furthermore, some fitting isneeded to enable easy after-market LED replacement. This inventionprovides such an arrangement and fitting.

SUMMARY OF THE INVENTION

A printed circuit board (PCB) base that has front and rear surfaces ismanufactured with laterally extending side-edge protrusions. Contactsurfaces are then provided on edge surfaces of the protrusions, forexample, by deposition. The PCB base may then be used to form a mountingsubstrate for the LED pairs.

One way to create the protrusions along the periphery of the base is tobore or route through-holes in the PCB with a pitch or indexingcorresponding to at least one internal mating surface of a lightfixture. By positioning the protrusions so that they mate with at leastone internal contact surface of a light fixture, this embodiment of theinvention may be used as an after-market replacement for existing lightbulbs designed for screw-in, bayonet, flanged, etc., fittings. Onealternative embodiment of the invention provides a base suitable forinstallation in a wedge-based fitting.

For fittings such as screw-in and bayonet fittings, etc., the base mayalso be provided with an arrangement for biasing the contact surfaces ofthe protrusions into electrical contact with the internal contactsurfaces of the fittings. One way to do this is to provide in the PCBbase at least one slot so as to form a region of lateral compression. Inthese cases, the PCB base should have a width equal to or slightlygreater than an internal dimension of the light fixture. Uponinstallation of the PCB base in the fixture, compression of the PCB basewill then create a lateral biasing force.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuit drawing of the simplest embodiment of an “AC LED”according to the invention.

FIG. 2 is a circuit drawing of a generalized embodiment of theinvention, including an LED array.

FIG. 3 is a plan view of a printed circuit board (PCB) from whichseveral PCB bases are manufactured for an embodiment of the inventionsuitable for use as an after-market replacement for light with a typicalscrew-in fitting.

FIG. 4 is plan view of a single PCB base separated from the PCB shown inFIG. 3.

FIG. 5 illustrates an example of a trace pattern used in the embodimentof the invention that provides an AC LED for screw-in fittings.

FIG. 6 shows an example of component layout on the PCB base illustratedin FIGS. 4 and 5, as well as how this PCB base can be screwed into atypical socket.

FIG. 7 is a side view of the arrangement shown in FIG. 6.

FIG. 8 illustrates a preferred way to spring-bias the PCB base of FIGS.4-7 so as to improve electrical contact between the base and thescrew-in socket.

FIG. 9 illustrates an embodiment of the invention suitable forafter-market installation in a wedge-type fitting.

FIG. 10 illustrates an embodiment of the invention in which two AC LEDsaccording to the invention are provided on a single PCB substrate.

FIG. 11 illustrates one example of how several LEDs of different colorsmay be mounted on a PCB base and electrically connected as in FIG. 2 soas to approximate a full-spectrum light source.

FIG. 12 is a side view of the arrangement shown in FIG. 11.

FIGS. 13 and 14 are side and top views, respectively, of a dual-elementAC LED according to the invention in a single capsule.

FIG. 15 illustrates an alternative layout of connectors and LED elementsfor the dual-element AC LED.

DETAILED DESCRIPTION

FIG. 1 is a circuit diagram that illustrates the fundamental embodimentof the invention: A pair of LEDs D⁺ and D⁻ are connected in parallel,with reverse polarity (with the anode of D⁺ connected to the cathode D⁻and the anode of D⁻ connected to the cathode of D⁺), in series with acurrent-limiting device, R, typically a resistor, and driven viacontacts k1, k2 by a power (or, equivalently, voltage or current) sourceS that delivers either alternating or direct current.

In applications that require illumination (such as reading lights) asopposed to simple indication (such as on/off), the LEDs D⁺ and D⁻ arepreferably of the super-luminescent type, for obvious reasons. Even aminimally skillful electrical engineer will be able to choose the actualtype of LEDs used, as well as the type and value of the resistor R, tofit the needs of a given application given the specifications of thepower source S, in particular, its peak delivered voltage.

Assume for the sake of illustration that when the source S suppliespositive voltage, current is flowing in the clockwise direction (viewedas in FIG. 1); negative output voltage therefore gives acounter-clockwise current flow. The operation of the LED pair D⁺ and D⁻then follows from the known properties of diodes: When the source S isproducing positive voltage, LED D⁺ will be forward biased and will lightup, whereas LED D⁻ will be reverse biased at the forward bias voltage ofD+ and will not give off light. The reverse voltage over D⁻ will be keptwithin safe limits (typically less than 4.0V for a white color LED andless than 2.0V for a red LED), at the forward bias voltage of D⁺, as D+will be conductive. Current through D⁺ will be limited by the resistorR. When the source voltage polarity switches, so too does the conductiveLED in the pair: D⁻ will become conductive and D⁺ will be reverse biasedat the forward bias voltage of D⁻. The two paired LEDs D⁺ and D⁻ thusoperate as a single “AC LED” in that, as long as the supply voltage isabove the minimum forward turn-on voltage, one LED of the pair willalways be producing light.

Some of the advantages even of the basic embodiment of the inventionshown in FIG. 1 are:

The only diodes required are those that actually produce light—norectifying elements are needed at all.

The invention will work whether the voltage source S deliversalternating or direct current. When operating with a DC voltage source,only one of the LEDs will be active, but on the other hand, the assemblyof only three components R, D⁺ and D⁻ will work equally well regardlessof the polarity of the voltage source S.

Each LED D⁺ and D⁻ is protected from reverse voltage breakdown by theother LED in the pair.

When operating with an AC voltage source, flicker is greatly reduced. Infact, at typical supply frequencies, for example, 60 Hz, D⁺ and D⁻ willboth appear as 120 Hz but totally out of phase with each other;therefore, little flicker will be apparent to a viewer at all.

When powered from an AC source, the peak current of each LED may reach avalue higher than the allowed continuous DC current. In such case, theLEDs will emit a higher peak brightness intensity while maintaininglower temperature than when driven at the maximum allowable DC current,which reduces the risk of damage and premature failure.

FIG. 2 illustrates a generalized embodiment of the invention: Ratherthan a single LED pair D⁺ and D⁻ being connected in parallel withreverse polarity, an m-by-n array 200 of such LED pairs D_(ij) ⁺ andD_(ij) ⁻ is provided (i=1, . . . , m; j=1, . . . , n), with m LED pairsconnected in series in each of n parallel paths.

A separate current-limiting device, R_(j), again, usually a resistor, ispreferably included in each parallel path in series with the LED pairs.Although not strictly necessary to the invention (a singlecurrent-limiting device could be used as shown in FIG. 1), this reducesthe load through any given resistor (for example) and allows forvariation in the number or characteristics of the diodes in eachparallel path. The value(s) of R_(j) may be chosen using normal designmethods, taking into account the number and characteristics of the LEDsand the properties of the voltage source S.

Each LED pair in the array may use the same diode type (and/or color)and be arranged the same as all other pairs, although this is notstrictly necessary as long as standard measures (such as adjusting theappropriate resistor values) are taken to ensure proper voltage andcurrent supply to the LEDs. In FIG. 2, the same number (m) of LED pairsis shown in each of the n parallel LED paths. This is not necessary tothe invention; rather, unequal numbers of LED pairs may be included indifferent paths—again, using separate resistors R_(j) in each pathfacilitates this option.

The operation of each pair of LEDs in the array will be the same asdescribed above for the single pair D⁺ and D⁻ shown in FIG. 1: At anygiven time, at most one LED in each pair will be forward biased andtherefore giving off light, the other being reverse biased and thereforeturned off.

FIG. 3 illustrates a standard printed circuit board (PCB) 100, fromwhich a plurality of bases are to be manufactured. For the sake ofsimplicity, only a single base 300 is described in detail. Any number(including a single one) of identical bases may be made from the PCB100.

As FIG. 3 shows, a plurality of through-holes or routes (illustratedusing a heavier lines 310-315, 330) are cut or bored through the PCB,preferably by conventional 1 mm routing, so as to form a plurality oflaterally extending protrusions 410-415, and preferably a bottomprotrusion 430, which extends out from the outer edge of the base 300.In the preferred embodiment of the invention, the routes are curved, atleast substantially semi-circular, although this is not essential andwill depend on the cross-sectional geometry of the threaded or slottedcontact surface of the fitting the base 300 is to be installed in (seebelow); thus, the protrusions could be right-angled or other have someother shape.

After routing, the routes 410-415, 430 are treated, preferably using astandard PCB plating process, to deposit an electrically conductivematerial such as copper on the inside, upper, and lower surfaces of theroutes. The PCB base 300 is then either punched out of the larger PCB100 by using a pre-designed punch-and-die set or scored and broken alongthe lines defining the rest (other than the protrusions) of theperiphery of the base 300. FIG. 4 illustrates the base 300 afterseparation from the PCB 100. In the figures, six side-edge protrusions410-415 are shown merely by way of example; the actual number used mayvary and in any given implementation of the invention will depend on theneeds of that implementation.

FIG. 5 illustrates one example of a pattern of traces T1, T2, T3 used tocreate the electrical connections symbolized in FIG. 1, with the tracescorresponding to the similarly numbered leads in FIG. 1. The dark dotsrepresent solder pads used to electrically connect component leads tothe traces. As part of plating the protrusions 410-415 some of theconductive plating material will be deposited on the inside, upper andlower surfaces of the base 300 as well so as to join with adjacentportions of the trace T3. The trace T3 will therefore be in electricalcontact with the inner surfaces of the protrusions. Similarly, theconductive material deposited on the bottom edge protrusion 430 will beelectrically connected to the trace T1.

FIGS. 6 and 7 illustrate one example of how the LEDs D⁺, D⁻ and thecurrent-limiting element (here, resistor) R can be mounted on the base300. In FIG. 6, the distance between the centers of the LEDs isindicated as d. This distance d should be kept as small as possible soas to reduce any parallactic optical effects when the user views thelight and thus to increase the impression that the LED pair is a singleAC LED. For example, when using standard 5 mm LEDs, which have adiameter of approximately 5 mm, d should be from five to eightmillimeters, and preferably from five to six millimeters; in otherwords, the LEDs should either just touch, or be no more than 3 mm apart,and preferably no more than 1 mm. FIG. 7 is a side view of the PCB 300with the components D⁺, D⁻ and R mounted.

Even though LEDs will typically generate less than 0.1 W of power each,applications such as those that have limited space but require highlight intensity also require very close packing of multiple LEDs. Inexisting arrangements, this leads to severe problems of heatdissipation. One advantage of connecting the LEDs in pairs (especiallyin the multi-LED embodiments of the invention shown below) to form an“AC LED” is that each LED is only “on” about half the time; this reducesgenerated heat and gives better opportunity for effective heatdissipation. Even disregarding the thermal advantages of the LEDs' 50%duty cycles, the invention still will operate much cooler than atypically halogen bulb, whose operating temperature is as high andpotentially dangerous as 200° C.

FIG. 6 also illustrates a screw-in fitting 600 typically used to receiveincandescent bulbs. Inner and outer dimensions (usually, diameters) ofthe fitting 600 are shown as wi and wo, respectively. The verticalseparation (viewed as in FIGS. 4-6), that is, the pitch p, of theprotrusions 410-415 is then chosen to match the pitch p of the internalcontact threading 610 of the screw-in fitting 600 the light is to beinstalled in.

The width w of the main portion (without the protrusions 410-415) of thebase 300 is preferably chosen to be the same or slightly less than theinner diameter of the screw-in fitting 600. When the base 300 is screwedinto the fitting 600, the helical inner contact surface 610 of thefitting will electrically contact at least one (and usually all) of theplated protrusions 410-413; the trace T1 will be electrically connectedwith the other contact 632 of the fitting via the protrusion contact430. In a different but preferred embodiment of the base 300, the widthw is preferably slightly greater than wi; this is described below inconjunction with FIG. 8.

FIG. 8 shows the preferred method according to the invention forproviding a lateral biasing force to increase the contact between theplated protrusions 410-413 and the inner contact surface(s) 610 of afitting: Using conventional techniques, slots 701, 702 are cut orpunched into the base 300 so as to preferably extend in the direction inwhich the base is installed in the fitting. In the illustrated example,the slots are therefore vertical. The illustrated slots are straight,but this is not required by the invention and will in many cases dependon the layout of traces. Curved slots are also possible, or slots with amore complicated geometry.

The width w of the main portion of the base 300 (not including theprotrusions) may then be slightly greater than the inner diameter wi ofthe fitting 600. When the base 300 is installed, for example, screwedin, it will therefore compress laterally, squeezing together the slots701, 702. The flexibility of the PCB material itself will bias theprotrusions 410-415 outward against the inner contact surfaces 610 ofthe fitting 600.

Another way to bias the base against the inner contact surface(s) 610 ofthe fitting 600 would be to mount an electrically conductive compressionspring (not shown) on the bottom protrusion 430 and to connect thisspring to the trace T1. The biasing force would then be vertical, whichwould tend to force the upper plated edges of the edges of theprotrusions 410-415 into physical and thus electrical contact with theinner contact surface (s) 610 of the fitting 600.

The invention is easily adapted for use in other types of fittingsbesides the screw-in fitting shown in FIG. 6. For example, using onlytwo plated protrusions, one on either side, the base 300 could be usedto fit into a standard bayonet fitting. By adjusting the verticalseparation (from zero upward) of the protrusions, and the base width,most standard bayonet fittings could be accommodated, regardless oftheir degree of indexing. A flanged base can also be created using asimilar technique.

The “AC LED” according to the invention may of course also be used infittings that do not require screwing in or rotation at all. FIG. 9illustrates, for example, how the base 300 may be formed so as to fitinto a standard wedge-type fitting. In this case, no special protrusionsare required at all. Rather, standard contacts 901, 902 are bonded ontothe PCB so as to contact the traces leading current from the twodifferent poles of the voltage source. The lateral separation of thecontacts 901, 902 will of course be chosen to match the positions of thefemale contacts (usually, spring-biased contacts in slots) into whichthe base 300 is to be fitted. Note that this embodiment of the base 300may be made exceptionally compact, in most cases little larger (andpossibly even smaller) than the incandescent bulb it replaces.

FIG. 10 illustrates just one of many different ways in which more thanone LED pair, in this case D₁₁ ⁺, D₁₁ ⁻ and D₂₁ ⁺, D₂₁ ⁻ may be mountedon a single base 300. Depending on the needs of the particularimplementation, the two pairs may be connected either in series(comparing with FIG. 2, m=2 and n=1) or in parallel (m=1 and n=2). Ifthe LED pairs are connected in parallel, then separate resistors R₁ andR₂ are preferably included, one in each path. Traces to supply currentto the LEDs may then be routed in any known manner, also depending onthe type of fitting the light is to be used in.

The usefulness of the configuration shown in FIG. 9 is more than simplythe doubling the number of LEDs active at any one time. One additionaladvantage is that it allows for front-and-back illumination coverage.Most common LEDs have up to approximately 50-degree illuminationcoverage; front-and-back mounting would therefore provide roughly100-degree coverage. The degree of coverage in any given implementationof the illustrated embodiment of the invention will of course depend onthe degree of coverage of the chosen LEDs.

It would also be possible to bend the leads of the LEDs, or to mountthem differently, so that they extend laterally out from the base 300rather than perpendicularly away from its surface.

Still another advantage arises in industries such as the automotiveindustry. Tail lights in a car are DC devices, but the fittings areusually polarized nonetheless, such that the invention, in particular,the base 300, would be able to fit in the fitting in only oneorientation. Because the invention provides an “AC LED,” polarity willnot make any difference. On the other hand, the “correct” orientation ofthe invention for a given car model, or in a given fitting (left asopposed to right, for example) might be such that a single LED pair, asshown in FIGS. 6 and 7, would be facing backwards. The twin-pair LEDarrangement of FIG. 10 would eliminate this concern.

Note that LEDs are typically so cheap that it would in most cases bebetter simply to have “idle” LEDs rather than having separate“left-handed” or “right-handed” bases. Rather than allow an LED pair toilluminate to no purpose (for example, the pair facing away from anypotential viewers), it would also be possible to route current to thetwo LED pairs through a switch (double-pole double-throw) so that onlyone pair is activated at any time; if the PCB is mounted “backwards”then the user can flip the switch and activate the other LED pair.

FIGS. 11 and 12 illustrate, respectively, top and side views of anembodiment of a multi-element, multi-path AC LED configuration thatprovides substantially full-spectrum light, at least at distances fromthe light assembly that users will normally be located for reading,working, etc. In this embodiment, several LEDs are mounted in any knownmanner so as to extend at least substantially perpendicular from a PCBbase 1100. Again, the LEDs are preferably mounted close together; asbefore, the LEDs should either just touch, or be no more than 3 mmapart, and preferably no more than 1 mm apart. LEDs are included thatemit three different wavelengths, that is, colors, preferably red, blueand green, (or any other combination of colors) which, when mixed, areperceived by a viewer as being full spectrum white. The LEDs arepreferably distributed so that no color clearly predominates in anyparticular region of the layout.

In this multi-color embodiment of the invention, the LEDs are preferablyconnected as reversed-polarity pairs as shown in FIG. 2, with aresistive element (labeled “R”) for each electrically parallel branch.Thus, the LEDs will be of six “types” D⁺ _(r), D⁻ _(r), D⁺ _(g), D⁻_(g), D⁺ _(b), and D⁻ _(b), that is, permutations of color (indicated bysubscripts r, g, and b for red, blue and green) and polarity.

All LED pairs emitting the same color may comprise one parallel branchof the configuration shown in FIG. 2, but this is not necessary. Rather,LED pairs of different colors may instead be connected in the sameparallel path; this would enable the full-spectrum light effect even inthe very unlikely event that one or more parallel paths were to fail. Itwould also be possible to include different numbers of LED pairs fordifferent colors so as to properly balance the luminance for each colorto create the most white effect; in this case, it is advantageous toseries-connect the LEDs of each color so that proper resistance valuescan be chosen in each parallel path.

At a typical user's normal reading or working distance from theassembly, the light from the LEDs will be so “mixed” that the user willnot be able to distinguish any red, green, or blue hues unless he islooking directly at the assembly. When looking at an illuminated objectlocated at distances beyond about 20 cm from the assembly, and possiblyeven closer, the user will perceive the mixture of red, green, and blueas pure white, or, rather, full-spectrum light illuminating the object.Contrast this with a conventional “white” LED, which is simply ablue-light LED coated with phosphorous so as to introduce a yellowcomponent to the spectrum and produce a “pseudo-white” color.

In one prototype of the multi-element embodiment of the inventionillustrated in FIGS. 11 and 12, the base 1100 was substantially round,with a diameter chosen so the base would fit and could be used as anaftermarket insert into common halogen fixtures. The illustratedembodiment is particularly advantageous for mounting within existingMR11 or MR16 fixtures with a bi-pin base and mirror reflector (hence the“MR”), or the smaller G4 fixture. The structures used to connect theLEDs electrically to the power supply will be chosen depending on whichtype of conventional lighting assembly is to be replaced.

It is of course not necessary for the LEDs in the multi-elementembodiment shown in FIGS. 11 and 12 to have different colors. Rather,all the elements could be of one color, such as white (for example,conventional “pseudo-white” LEDs), red (for example, for cockpits orboats or other environments where good night vision is important), orany other wavelength, including non-visible wavelengths. A simpleswitching mechanism could also be included to allow the user to switchbetween colors, for example, between white and red. Because theAC-coupling of LED pairs according to the invention enables them tooperate much cooler than standard DC LEDs and in general much coolerthan standard incandescent and halogen bulbs, even dozens of LEDs(single or multi-color) can be densely mounted on a single base 1100 andprovide light as bright or brighter than the bulbs being replaced, yetat lower temperature.

FIGS. 13 and 14 are side and top illustrations of an embodiment of theinvention in which reverse-polarity LED elements (dies) 1301, 1302 areencapsulated in a single casing 1300. In FIG. 14, the standard diodesymbols are included on the dies 1301, 1302 merely to show that thesesemi-conductive elements are connected with reverse polarity.Electrically conductive legs/leads 1320, 1322 extend into the casing, onone of which (leg 1320) the LED dies are mounted by conventional bondingmethods. Two connecting wires are included for each element to connectit electrically to legs 1320 and 1322 and to complete the electriccircuit from the power supply (not shown here) through the LEDs.Connecting wires 1312, 1313 are labeled in FIG. 13 for the element 1302;four connecting wires are shown in FIG. 14, two for each element 1301,1302.

By including the two parallel connected, reverse-polarity LED dieswithin a single casing, a single component is provided that implementsthe AC LED according to the invention. Such a component could be used toimplement any LED pair described in any embodiment of this invention.

FIG. 15 shows an alternate configuration of the common-casing, AC LED,in which each element in the pair is mounted on a different one of thelegs, with a respective connecting wire connecting the element to theopposite leg. One advantage of this structure is that the leg/die/wireconfiguration for each “side” is identical to the other, differing onlyin its mounted orientation within the casing. This simplifiesmanufacture, since only one arrangement is needed.

1. A contact surface arrangement for a printed circuit board (PCB) formounting at least one electrical component comprising: a base cut from aPCB substrate; at least one lateral base protrusion mating with at leasta first internal, at least partially electrically conductive, surface ofa pre-existing, commercially available fitting; an electricallyconductive material deposited on an outer edge of the lateral baseprotrusion; at least one electrically conductive trace on a planarsurface of the base, the trace being in electrical contact with theelectrically conductive material deposited on the lateral baseprotrusion so as to create a first electrical path to at least one ofthe electrical components; and at least one slot in the base extendingin an axial direction of the fitting; in which the base is wider than aninternal diameter of the fitting, but by no more than a total width ofthe slit(s), such that the base, upon installation in the fitting,biases the lateral base protrusions outward and into contact with thefirst internal surface of the fitting; in which: the electricalcomponent is a light-emitting diode and the fitting is a standardfitting designed to receive an incandescent light bulb by insertion ofthe bulb in an axial direction; and the standard fitting is a screw-infitting and the internal surface has threading with a pitch; and oneither side of the base portion, the holes and thereby the lateral baseprotrusions have the same pitch as the pitch of the threading.
 2. Acontact surface arrangement for a printed circuit board (PCB) formounting at least one electrical component comprising: a base cut from aPCB substrate; at least one lateral base protrusion mating with at leasta first internal, at least partially electrically conductive, surface ofa pre-existing, commercially available fitting; an electricallyconductive material deposited on an outer edge of the lateral baseprotrusion; and at least one electrically conductive trace on a planarsurface of the base, the trace being in electrical contact with theelectrically conductive material deposited on the lateral baseprotrusion so as to create a first electrical path to at least one ofthe electrical components; in which: the electrical component is alight-emitting diode; the fitting is a standard fitting designed toreceive an incandescent light bulb by insertion of the bulb in an axialdirection; the standard fitting is a screw-in fitting and the internalsurface has threading with a pitch; and on either side of the baseportion, the lateral base protrusions have the same pitch as the pitchof the threading.